


ammonia

by supernormal



Category: Dr. STONE (Anime), Dr. STONE (Manga)
Genre: Crushes, Getting Together, Humiliation, M/M, Omorashi, Praise Kink, Trans Male Asagiri Gen, gen loves him anyway, more douchy pervert senku because i love that shit, of course the ending is soft i can't not make it soft it's not in me, pissing in a cup, though the identity of his genitals are only referenced like twice lmao
Language: English
Status: Completed
Published: 2020-05-02
Updated: 2020-05-02
Packaged: 2021-03-01 21:35:22
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,633
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/23960173
Author URL: https://archiveofourown.org/users/supernormal/pseuds/supernormal
Summary: senku coaxes ammonia out of gen. with cola, of course
Relationships: Asagiri Gen/Ishigami Senkuu
Comments: 5
Kudos: 75





	ammonia

**Author's Note:**

> there's a sengen omorashi tag [#千ゲomrs企画GW編](https://twitter.com/search?q=%23%E5%8D%83%E3%82%B2omrs%E4%BC%81%E7%94%BBGW%E7%B7%A8&src=typed_query) going around on jp twitter for event someone organized for golden week, so i figured i’d finish and post this fic from january

“Come here, mentalist.”

Gen skipped over inside the lab to meet Senku.

“What is it, Senku-chan?”

“I have something for you.”

He shut the door, leaving just the two of them inside with nothing but the afternoon sunlight streaming in through the small windows. Senku went to the back to retrieve a tray with two brand new bottles of Senku cola resting on it.

Gen’s face lit up.

“Ah! Senku-chan! For me? Thank you so much!”

“Yep.”

Gen giddily took one off the tray and noticed that Senku had even chilled it in advance for him. He wrapped both his hands all the way around the bottle to savor the feeling of the cool glass, something that was now a luxury. He took a sip and hummed in delight at the familiar taste.

Senku smirked at how eagerly Gen proceeded to chug it down, like he hadn't drinken anything in days.

“Oi, Gen. Why don't you hang out in here for a bit?”

“Of course, Senku-chan!” He took a seat, still holding the bottle to his lips. “So, whatcha up to?”

Senku began to explain his new project, some chemical concoction with details that completely flew over his head. The excitement he radiated while he explained it was as endearing as ever though. Gen couldn't stop grinning as he continued to sip on his drink. 

_Senku-chan is so cute whenever he’s in his element._

He was really happy about Senku asking him to hang out. Maybe Senku was beginning to warm up to him. Maybe he wanted to be better friends. Maybe he… no, it couldn't be… Unless?

They made small talk for a while, with Senku standing at the counter fiddling with some beakers and Gen sitting cross legged on a chair, drinking his cola. They reminisced about their favorite TV shows and games, complained about the villagers’ antics, and spoke excitedly about the first things they’d do once civilization was restored.

Gen popped the cork off of the second bottle. It was a hot day, and before he knew it he had gulped down the whole thing. He noticed Senku look at him over his shoulder, grinning and eyeing him up and down as if he were checking him out.

_Huh. Guess he’s just happy I like it._

They continued to chat. Senku told him about the multiple times he almost burned his apartment down and Gen recounted stories about his studies in America.

Gen finished the second bottle after about 45 minutes in. He was kind of disappointed that he drank all of it so fast, but maybe Senku would make him more later.

Another fifteen minutes or so later, Senku motioned for him to come over.

“Hey, check this out.”

Gen went to go stand next to him, his sleeves curiously put together in his trademark fashion.

He poured a test tube of a blue liquid into a beaker full of a clear one. Gen watched in interest as the whole solution turned purple after they had mixed.

“Ooh!”

“Pretty neat, right?”

“Uh-huh.”

As he peered at the liquid, he noticed the stinging sensation in his bladder. He had been so caught up in Senku’s presence that he hadn't noticed how full his bladder was from those two bottles of soda. He figured he should excuse himself to go piss somewhere secluded in the forest behind the lab.

Just as he was about to leave, Senku caught him off-guard by wrapping his hand around his waist and pulling him close to his side.

He spoke to him in an uncharacteristically low voice.

“Hey. Can you do something for me?”

Gen’s felt his heart thumping in his chest.

“W-what is it?”

Senku grabbed a clean glass from off the counter.

“Pee in this cup for me.”

“Eh?”

“Piss in the cup.”

“W-why?”

“Ammonia. I need your ammonia. For this project. I ran out.”

“Uh, can't you do it yourself?”

“I don't have to go right now.”

“Then wait until you do.”

“Oh, come on. It won't take long. Here, do it in this.”

Senku placed the cup down on a stool. He stepped behind Gen and began to soothingly massage his shoulders and run his fingers through his hair. Gen felt his face heat up and goosebumps spread around his body.

_Shit, why does he have to be so charming?_

“You can do this, right? You'll be helping me out so much.”

“It’s so embarrassing, though…” Gen whined.

“Hey, hey, don't worry. It’s just me here. I don't judge. What do you say?”

“Mm… Are you sure I can't go outside and do it there? Just give me the cup and I’ll bring it back.”

He waved his hand dismissively.

“Ahh, people will see you. And it's a pain in the ass. We're already in here, right? Plus, it'll be better if I can watch you do it. If there's any problems I'll be able to catch them.”

Gen knew he was totally bullshitting that last part. He just wanted to watch him pee.

“Okay, fine…” He pulled down his pants to his knees and hesitantly stood over the cup.

_“Up you go!”_

Without warning, Senku had grabbed Gen by the waist and hoisted him up, then shuffled his arms down to hold him by his legs, one hand supporting each thigh. Gen instinctively reached back to hold onto him for more balance. 

_“Kyaa!_ What are you doing?”

“It'll be quicker and easier this way.” He chuckled as he playfully twirled him around, making him squeal. Gen normally would have welcomed this but he _really, really, really_ fucking had to go right now, and being shaken around like that wasn't helping at all.

“You're so light. S’cute.”

Gen grumbled in annoyance. His heart was beating like crazy. And he _really_ had to piss now. With every breath he took, his bladder screamed at him to relieve himself.

Senku moved his arm down to rest on his stomach. Gen winced at how badly even just Senku gently touching it made him want to burst.

“Okay,” he panted, “hurry up and let me go.”

”Alright,” Senku tightened his grip around his thighs. “Spread your legs,” he commanded.

Gen bit his lip and spread them as wide as he could.

Senku sighed in satisfaction.

“Oh my God, you have no idea what an amazing sight this is right now,” he groaned.

Gen felt Senku’s hard-on bulging through his tunic and poking him from behind. He bit his lip. _He's really getting off to this shit._

Gen screwed his eyes shut. Senku whispering in his ear combined with him squeezing down on his bladder and having him spread his legs like that was too much. He was about to burst.

“You ready?”

He shakily nodded.

Senku held his pussy directly over the cup.

“Just relax,” he whispered, accompanied by an especially sharp push on his stomach.

His urine rushed out in a forceful stream that messily splashed in the cup as it filled.

Gen moaned as the relief washed over his entire body. He held on to Senku tighter, grasping hard at his leather shirt.

_“O-ohh!”_

“Aha! There we go. I knew you could do it. Good boy,” Senku praised.

The stream of piss wasn't showing any signs of slowing down. Gen opened his eyes to watch the cup steadily fill.

“You’ve got good aim,” Senku joked. He was so close to him, Gen could feel his breath on his ear as he teased him.

_“Mmnh…”_

As his bladder emptied the stream weakened to a dribble.

“Almost done?”

“Mhm,” he breathed.

Gen essentially went limp. The feeling of having all that pressure finally released was amazing. He let Senku keep holding him for a moment while he caught his breath.

“Okay… Senku-chan… There you go… Happy now?” It was a struggle to form a coherent sentence.

“Not yet. Still have to let you drip dry,” Senku cooed in his ear.

Gen groaned as Senku-spread his legs further apart. Being held in such a vulnerable position made his heart pound like crazy. The last drops fell into the cup, the interval of time between them gradually lengthening.

Finally, the last one fell, leaving the vessel full nearly to the brim.

“Ah… See? There we go. That wasn't so bad, was it?”

“Ugh…”

“Here, I’ll let you down now.” He gently lowered him to the ground, but Gen completely failed to stay on his feet and collapsed onto the floor as a blushing mess with his pants still pulled down all the way.

Senku crouched down to face him. He had a smug grin stuck to his face.

“No, seriously. That was great. You really made a lot.” He reached out to tussle his hair. “I think I’ve found my new permanent source of ammonia,” he laughed.

Gen covered his face with his hands. He felt like he was about to explode with embarrassment.

Senku grabbed his wrists and pulled them away from his face.

“Aw, are you mad at me? I'm sorry.”

Gen couldn't help but smile really wide. This guy is just too much.

“N-no, it's just… God, Senku-chan. I really cannot believe you're into that.”

Senku smiled back at him. “Yeah, me either.” He patted his head again. “But don't worry. I’ll make you all the cola in the world, okay?”

“Senku-chan, I don't need that. Can you just stay with me here for a bit, please? M-my knees are too weak to stand right now.”

“Pfft. Sure.” Senku sat down cross-legged, looking at Gen fondly.

_Oh. Right._

Senku still had a massive erection. Gen stared in awe at the bulge at his crotch. He noticed that he was soaking wet down there himself, and it wasn't just from the urine.

“So… uh… I see that you…”

“Yes.”

“Do you want to…”

“Yes.”

**Author's Note:**

> left the ending kinda ambiguous. its either they jerked off together, jerked each other off, or fucked. choose your own adventure
> 
> inspired by some really really really good omo sengen fanart from awhile ago. don't remember the artist so i can't link it lol. this fetish isn’t one of my faves; i’m not usually into piss but oh my god, this pairing makes so many fetishes so appealing to me. sengen has given me so many kinks jfc.
> 
> i’ve never written piss/omo or even read a piss fic so bear with me if the writings weird i didn't have any “influences” to go off of hope it read okay


End file.
